Surgical procedures and traumatic injuries are often characterized by massive blood loss. Conventional approaches such as manual pressure, cauterization, or sutures may be time consuming and are not always effective in controlling bleeding.
Over the years, a number of topical hemostatic agents have been developed to control bleeding during surgical procedures and to control bleeding resulting from traumatic injury. Some agents such as collagen-based powders, sponges, or cloths are of a particulate nature. Particulate hemostatic agents provide a lattice for natural thrombus formation, but are unable to enhance this process in coagulopathic patients. Microfibrillar collagen, a particulate hemostatic agent, comes in powder form and stimulates the patient's intrinsic hemostatic cascade. However, this product has been reported to embolize and induce a localized inflammatory response if used during cardiopulmonary bypass. Pharmacologically-active agents such as thrombin can be used in combination with a particulate carrier, for example, as in a gelfoam sponge or powder soaked in thrombin. Thrombin has been used to control bleeding on diffusely bleeding surfaces, but the lack of a framework onto which the clot can adhere has limited its use. The autologous and allogenic fibrin glues can cause clot formation, but do not adhere well to wet tissue and have little impact on actively bleeding wounds.